NCERT 11TH STANDARD BIOLOGY – STRUCTURAL ORGANISATION IN PLANTS AND ANIMALS The description of the diverse forms of life on earth was made only by observation – through naked eyes or later through magnifying lenses and microscopes. This description is mainly of gross structural features, both external and internal. In addition, observable and perceivable living …
NCERT 11TH STANDARD BIOLOGY – STRUCTURAL ORGANISATION IN ANIMALS In unicellular organisms, all functions like digestion, respiration and reproduction are performed by a single cell. In the complex body of multicellular animals the same basic functions are carried out by different groups of cells in a well organised manner. The body of a simple organism …
NCERT 11TH STANDARD BIOLOGY – SECONDARY GROWTH The growth of the roots and stems in length with the help of apical meristem is called the primary growth. Apart from primary growth most dicotyledonous plants exhibit an increase in girth. This increase is called the secondary growth. The tissues involved in secondary growth are the two …
NCERT 11TH STANDARD BIOLOGY – ANIMAL KINGDOM – CLASSIFICATION OF ANIMALS The broad classification of Animalia based on common fundamental. The important characteristic features of the different phyla are described. Phylum – Porifera Members of this phylum are commonly known as sponges. They are generally marine and mostly asymmetrical animals. These are primitive multicellular animals …
NCERT 11TH STANDARD BIOLOGY – PLANT KINGDOM – BASIS OF CLASSIFICATION Inspite of differences in structure and form of different animals, there are fundamental features common to various individuals in relation to the arrangement of cells, body symmetry, nature of coelom, patterns of digestive, circulatory or reproductive systems. These features are used as the basis …
NCERT 11TH STANDARD BIOLOGY – MORPHOLOGY OF FLOWERING PLANTS The wide range in the structure of higher plants will never fail to fascinate us. Even though the angiosperms show such a large diversity in external structure or morphology, they are all characterised by presence of roots, stems, leaves, flowers and fruits. For any successful attempt …
NCERT 11TH STANDARD BIOLOGY – FROGS Frogs can live both on land and in freshwater and belong to class Amphibia of phylum Chordata. The most common species of frog found in India is Rana tigrina. They do not have constant body temperature i.e., their body temperature varies with the temperature of the environment. Such animals …
NCERT 11TH STANDARD BIOLOGY – FLOWER FAMILIES , FLORAL FORMULAS Fabaceae This family was earlier called Papilionoideae, a subfamily of family Leguminosae. It is distributed all over the world. Vegetative Characters Trees, shrubs, herbs; root with root nodules Stem: erect or climber Leaves: alternate, pinnately compound or simple; leaf base, pulvinate; stipulate; venation reticulate. Floral …
NCERT 11TH STANDARD BIOLOGY – EARTHWORM Earthworm is a reddish brown terrestrial invertebrate that inhabits the upper layer of the moist soil. During day time, they live in burrows made by boring and swallowing the soil. In the gardens, they can be traced by their faecal deposits known as worm castings. The common Indian earthworms …
NCERT 11TH STANDARD BIOLOGY – COCKROACH Cockroaches are brown or black bodied animals that are included in class Insecta of Phylum Arthropoda. Bright yellow, red and green coloured cockroaches have also been reported in tropical regions. Their size ranges from ¼ inches to 3 inches (0.6-7.6 cm) and have long antenna, legs and flat extension …